NeverEnough007

Plus, an exhaust alone may bet about 10hp as well but, when you combine the 2, you may end up with 25-30hp. Add a tune to that and you are doing ok! It is all about the mods working with eachother to create a multiplier effect.

Rochester

iTrader: (8)

I suspect most people are pleased with their aftermarket intake, regardless of cost or gains (or loss).

blnewt

iTrader: (13)

I know I am
It's pretty common knowledge that "intakes+VQ=addicting sound" and if you like the looks than that's a nice bonus, if you're after anything significant HP-wise than you'd better really open your wallet

RexHavoc

iTrader: (7)

^^^^
+1 here. I "feel" like there have been some gains, though minor, but it could also be that I'm enjoying it just a little more with the change in sound.

Rochester

iTrader: (8)

No, that's not even remotely accurate.

Manufacturer claims of HP gains are always optimistic. Irrespective of that, HP gains from Intake + Exhaust components are never cumulative, they are marginal at best. In fact, without a tune, and depending on the car and the parts, you could even be sacrificing HP while chasing a particular sound.

Also, HP gains at the curve are kind of meaningless for a daily driver (IMO). I'd rather lose peak HP and gain mid-range.

Tim30250

Unfortunately, that's true. Not only are gains from bolt-on mods marginal, but they are also diminishing. Even if you confirmed 10 HP from an intake and 10 HP from HFCs, independently - they wouldn't provide 20 HP cumulatively, perhaps 13-15 HP if you're lucky.

Regardless, modding is fun, and this thread is very interesting. Thanks again to Alfredo for taking the time to test and post up each result!

NeverEnough007

Not sure where you guys get that idea. If you have a restricted exhaust, your car will only suck in so much air regardless of intake. Freeing up the exhaust allows more air flow through the motor. This give the "green light" for the motor to gulp more air from the intake. This has been proven on the dyno in other models I have owned. Maybe there is less relevance on the G since our intake and exhaust is already relatively open. Adding the tune allows you to break past the guard rails on factory settings giving more flow.

GoFightNguyen

iTrader: (14)

I'm not 100% sure if I agree with this. The G37 has a VQ37VHR motor in it, with a displacement of 3.7 liters. It gulps 3.7 liters of air. The density of that air is what people are trying to increase, either by getting it colder (CAI's), or compressed (SRI and FI). It's not like open intakes make the engine pull 3.8 liters of air, or 4.0 liters of air. The engine takes as much as it takes.

Mad Oregonian

I think what he's trying to say is that by increasing efficiency at both ends one can increase the overall efficiency of the motor, thereby increasing power output. This is forever going to be hotly debated but at the end of the day someone has offered to give us a real world running total of his dyno readings as he mods his car, that will be where the rubber meets the (rolling) road for this discussion, until then all that is being passed out are opinions.

Rochester

iTrader: (8)

Pragmatic, real-world experience. The OEM exhaust and intake setup on the VQHR are pretty efficient already, so all I can recommend is that you don't get carried away with the unrealistic expectations of conventional wisdom.


What? No, there is no contention, no hot debate. There's just reality, and the ginned up expectations of people who modify their cars. And while it's very cool Alfredo has tasked himself with this mod/dyno regimen, people have been modifying the VQ platform for decades. Pretty sure no one is waiting for Alfredo to be the first one to modify a NISSAN, for crying out loud.

No offense, OP. This is a fun thread. Please continue.

NeverEnough007

Exactly. The results will differ in different makes and models of course but, our cars still have bottlenecks in efficiency that hamper the motor. These are not carbureted motors, very sensor is connected and working in unison to create efficient power. There are a lot of NA vq35hr build threads out there and most of their learnings apply here.

alfredo24pr

iTrader: (1)

lol. dynos are with 91 octane btw

Daddy Fat Sacs

iTrader: (15)

subscribed.....alfred..any other plans on mods besides cai and the hfc? I would assume cbe would be next?

Rochester

iTrader: (8)

...after which, maybe the Motordyne M37 Intake Manifold before a tune?

Other than 4.083 gears, and weight reduction, doesn't that pretty much wrap up NA power mods?

Intake + UIM + HFC + CB + Tune =

GoFightNguyen

iTrader: (14)

Don't forget a pulley swap, drive shaft switch, and light wheels.